Laboratory diagnostic methods are the main tools in the practice of a doctor of any specialty, including an endocrinologist. Factors were identified that could change the concentration of the biologically active fraction of the test substance, subsequently complicating the interpretation of laboratory results and making the right clinical decision. The literature describes a variety of circulating autoantibodies involved in binding to pituitary hormones (prolactin (PRL), thyroid-stimulating hormone (TSH), growth hormone, luteinizing, follicle-stimulating, and adrenocorticotropic hormones), hypothalamus (vasopressin and oxytocin), pancreas (insulin and glucagon) , parathyroid glands (parathyroid hormone), as well as with thyroid hormones. As a rule, the resulting macromolecules lead to an increase in laboratory parameters, in which the prevailing fraction of the hormone does not have biological activity, which determines the main problem of this phenomenon. The most common variants include immune complexes with PRL and TSH, causing the phenomena of macroprolactinemia and macrothyrotropinemia (macro-TSH-emia/macro-TSH), respectively. Most laboratory test systems used in clinical practice are capable of determining only the total amount of PRL and TSH. The presented clinical observation describes a combination of the phenomena of macro-TSH and macroprolactinemia in a patient with autoimmune thyroiditis (AIT) and vitiligo.

BACKGROUND: True gynecomastia is associated with excess body mass, which is caused by an imbalance of androgens/estrogens. Therefore, there is an interest in evaluating the possibility of drug therapy for this condition through the use of antiestrogens or aromatase inhibitors.AIM: To evaluate the possibility of drug therapy for true gynecomastia in adult men with excess body mass through the use of clomiphene or letrozole.MATERIALS AND METHODS: A retrospective study included men with newly developed gynecomastia and excess body mass who sought medical help at the Endocrinology Research Center from January 2020 to May 2024, and received either clomiphene therapy or letrozole for a period of 4 weeks. All patients were evaluated for the condition of their breast glands, total bilirubin, liver transaminases, creatinine, urea, luteinizing hormone, prolactin, sex hormone-binding globulin, estradiol, total testosterone, alpha-fetoprotein, and chorionic gonadotropin. The baseline level of statistical significance was set at p<0.05.RESULTS: With clomiphene treatment, no statistically significant differences were found in the evaluated parameters, except for estradiol and testosterone levels, which increased. Clomiphene therapy worsened the condition of three patients (13% (95% CI 2,8;33,6)) - they experienced breast pain that was not present at the time of prescription. With letrozole treatment, there was a positive trend - all evaluated parameters significantly improved. Comparing the changes in the studied parameters, it was found that letrozole treatment had a better effect in terms of the severity of gynecomastia (-1[0;-1] degree), reduction in estradiol levels (-31,7[-8,8;-90,8] pmol/l), and also reduced the number of patients willing to undergo surgical removal of gynecomastia (-63,4% (95% CI -46,9;-77,9)).CONCLUSION: The use of an aromatase inhibitor reduces the severity of gynecomastia and decreases the number of patients willing to undergo surgical removal.

BACKGROUND:In recent years, the incidence of gynecomastia in adult men has increased significantly. It is of interest to study the specific features of the disease in these patients. AIM:To identify the main characteristics of acute gynecomastia in adult men. MATERIALS AND METHODS:A continuous one-stage study including 160 adult males with acute onset gynecomastia, who were he was treated in Endocrinology Research Centre, Moscow. Total bilirubin, hepatic transaminases, creatinine, urea, luteinizing hormone, prolactin, sex hormone binding globulin, estradiol, total testosterone, alpha-fetoprotein, chorionic gonadotropin and mammary gland condition were evaluated in all patients. Baseline significance threshold level of p&lt;0.05. RESULTS:The incidence of gynecomastia increased from 5,4% in 2020 to 14,4% in 2024. Tumor forms of gynecomastia were rare, with 1,2% (95% CI 0,0; 3,0) of cases. In 30% (95% CI 22,9; 37,1) of men, gynecomastia was due to the intake of anabolic steroids for athletic stimulation. In 11,2% (95% CI 6,4; 16,1) of patients, gynecomastia was hepatogenic. In 7,5% (95% CI 3,4; 11,6), it was due to elevated sex hormone binding globulin. 47,5% (95% CI 39,8; 55,2) were endocrine non-tumorigenic form of gynecomastia due to excess body weight with formation of changes in sex hormone levels. The patients who took anabolic steroids were characterized by young age, as well as decreased luteinizing hormone levels and increased testosterone levels. The group of patients with elevated sex hormone binding globulin had no clinically significant features. Men from the group of hepatogenic gynecomastia were characterized by hyperestrogenism. Patients in the group with altered sex hormone levels were characterized by high body mass index and either increased estradiol or decreased testosterone or a combination of both. CONCLUSION:The number of adult male patients with acute gynecomastia is progressively increasing. In the examined sample of patients, the main causes of gynecomastia were patients taking anabolic steroids, liver dysfunction and weight gain with the formation of changes in sex hormone levels. Patients taking anabolic steroids were characterized by a drug--induced increase in testosterone and estradiol levels, which was accompanied by suppression of pituitary gonadotropic function. Estradiol elevation was also characteristic of patients with hepatogenic form of gynecomastia and men with excess body weight with formation of changes in sex hormone levels.

BACKGROUND:The diagnostic value of calcitonin measurement in fine-needle aspiration biopsy wash-out fluid is a promising tool in the diagnosis of medullary thyroid cancer. AIMS:We assessed the potential usefulness and the diagnostic significance of Ct-FNAB alone in comparison with cytology in the diagnosis and localization of primary or metastatic MTC. MATERIALS AND METHODS:For this purpose, we retrospectively examined data from 67 patients with suspicious thyroid nodules and/or lymph nodes who ultimately underwent surgical treatment at the Endocrinology Research Centre in 2015-2020. The primary endpoint of the study was to evaluate the diagnostic accuracy of Ct-FNAB when compared to cytological examination. The secondary endpoint was to determine the optimal diagnostic level for use in clinical practice. RESULTS:The obtained results showed that high Ct-FNAB concentrations were present in all histologically proven MTC, either in thyroid gland (sensitivity 92.5%, specificity 100%) or neck masses (sensitivity 88.5%, specificity 100%). The optimal diagnostic threshold for Ct-FNAB values from thyroid nodes was &gt; 122 pg/ml, from lymph nodes &gt;35.8 pg/ml. CONCLUSIONS:Our findings suggest that Ct-FNAB is a highly reliable diagnostic procedure to identify primary and recurrent/metastatic MTC. The actual relevance of this technique in the management of MTC needs further longitudinal studies in a larger number of patients.

BACKGROUND Clinical diagnostic laboratories (CDL) have at their disposal various automated systems for the measurement of biochemical parameters and markers such as prolactin. Each of the test systems manufactures offers its own alternate design of the method, which makes standardization difficult. In endocrinological practice, the problem of result discrepancies often arises. In hormonal assays, the clinical picture of patients sometimes does not correspond to the reference values provided by the manufacturers, which determines the need to develop the method-specific reference values for a specific population. The difficulty in interpreting basal prolactin levels is not only due to a transient increase in the hormone levels caused by stress or excessive physical exertion, but also due to a significant variability of indicators in the same patient, even if all recommendations for blood sampling are followed. AIM The aim of the study to determine the reference values in serum samples of women, men and children of different age groups for the VITROS Immunodiagnostic Systems and compare the results with the "expected prolactin levels" recommended by the method manufacturerMATERIALS AND METHODS: The monocentric study included 879 serum samples of apparently healthy subjects who were admitted to the Endocrinology Research Center. Measurements were performed using the VITROS ECi 3600 automatic chemiluminescence analyzer (Ortho-Clinical Diagnostics, Great Britain). RESULTS For adult men and women reference values were 66-436 and 94-500 mIU/l respectively. When comparing the results of prolactin determination in women and men of the studied cohort with the "expected values" of the VITROS ECi 3600 manufacturer a systematic shift towards an increase in lower and upper limits of the reference values was found in both -cohorts. CONCLUSION The obtained reference values of prolactin can be use in the determination of prolactin in the Russian population for VITROS ECi 3600 Immunodiagnostic Systems.

The study objective is to compare pre- and intraoperative characteristics, and the results of neurosurgical treatment in patients with Cushing’s disease, non-visualized adenoma and microadenoma of the pituitary gland.Materials and methods. The results of transsphenoidal adenomectomy were analyzed in 102 patients with non-visualized corticotropinomas and 360 patients with microcorticotropinomas. The pituitary genesis of endogenous ACTH-dependent hypercorticism in 182 patients was proved by the results of selective blood sampling from inferior petrosal sinus with stimulation desmopressin. The study included 369 women and 93 men aged 16 to 64 years. All patients were operated by transnasal approach using endoscopic techniques.Results. The group with non-visualized adenoma was dominated by men (p = 0.005) and patients with severe hypercorticism (p = 0.021). When comparing intraoperative characteristics in this group, invasive growth was statistically significantly more frequent (53 % vs 39 %) (p = 0.017), which in turn led to more aggressive intraoperative tactics (p <0.001) and more frequent development of hypothyroidism (11 % vs 4 %) (p = 0.028) in the early postoperative period. Early postoperative remission occurred in 73 (72 %) of 102 patients with non-visualized adenoma and in 314 (87 %) of 360 patients with microadenoma (p <0.001).Conclusion. Early results of primary transsphenoidal adenomectomy in patients with non-visualized pituitary adenoma were significantly worse in comparison with patients with microadenoma detected by 1.5 T magnetic resonance imaging, which have more frequently invasive growth, what leads to an increase in the volume of surgery and a possible increase in postoperative hypopituitarism.

Primary aldosteronism (PA) is the most common form of secondary arterial hypertension. In patients with PA, more so than in the general population, there is a prevalence of insulin resistance, diabetes mellitus, metabolic syndrome, osteoporosis, and symptoms of depression; these conditions are more likely to manifest a gluco- rather than mineralocorticoid excess. This fact is of particular importance in light of recent studies that have shown that PA is often associated with glucocorticoid excess. Since the first reports of cases of combined secretion of aldosterone and cortisol in 1979, the number of cases of so-called Connshing syndrome has increased. An analysis of data from recent studies suggests that hypercortisolism in PA is closely associated with an increased risk of cardiovascular complications, metabolic disorders and post-surgical adrenal insufficiency. The most important diagnostic problem in adenomas with combined secretion is the risk of false interpretation of the results of adrenal venous sampling (AVS). The indications that suggest aldosterone-and-cortisol-co-producing adenoma are the lack of suppression of cortisol levels following a night test with 1mg of dexamethasone, and an adrenal tumo of over 2.5cm. As an alternative test capable of differentiating this type of tumor, a number of researchers have proposed measuring the level of so-called hybrid steroids in the peripheral plasma and urine. Taking into account the high prevalence and potential risks, ruling out of excess corisol secretion is obligatory in all cases of PA before AVS and when planning surgery.

Primary hyperaldosteronism (PA) - is the clinical syndrome, results from autonomous of the major regulators of secretion, aldosterone overproduction by a tumorous or hyperplastic tissue in adrenal cortex. Being the most frequent cause of secondary hypertension, PA may be represented by disorders with unilateral or bilateral aldosterone overproduction and differential diagnosis between them is crucial for choosing a right therapeutic approache: lifelong medical therapy with mineralocorticoid receptor antagonists or unilateral adrenalectomy. Adrenal venous sampling (AVS) is currently the «gold standard» test for identifying laterality of excess hormone production, unlike imaging tests, sensitivity and specificity of which is not enough, due to inability to evaluate functional activity with confidence, and also to limitations in detecting tiny abnormalities of adrenals, such as microadenoma or hyperplasia. Excluding certain cases, AVS is recommended to patients with confirmed PA, planning surgical treatment, to determine the lateralization of aldosterone hypersecretion. Described clinical case of patient with confirmed lateralization from adrenal without any detected lesions on CT-imaging and nonfunctioning tumour on contralateral side, highlights the importance of using AVS for decision to refer patients for surgery.

The testosterone is a key element of hypothalamus hypophysis gonad system. Its physiological role in males is well known and consists primarily in formation of male phenotype and support of spermatogenesis. The evaluation of androgenic status is necessary in case of such wide specter of clinical symptoms and pathological states as hypogonadism, delayed of premature puberty, polycystic ovary syndrome, particular types of cancer, etc. The precise measurements of testosterone concentrations have a decisive value in case of receiving biochemical data for supporting clinical decisions at diagnostic, treatment and prevention of androgenic diseases. The purpose of the study is to carry out a comparative analysis of the results of detection of testosterone in blood serum using analyzers Architect 2000 and Vitros 3600 and applying technique of highly-effective fluid chromatography - a tandem mass-spectrometry. The analysis was applied to samples of blood serum from 230 patients send to the endocrinological research center of Minzdrav of Russia. The comparative analysis of the results of detection of concentrations of testosterone demonstrated consistent difference in absolute values. However, a statistically significant correlation (р < 0,05) between values of testosterone obtained by different techniques was established. The correlation coefficient in different groups of patients made up to 0,894-0,920 and 0,955--0,965 correspondingly to comparing the results of Architect and Vitros and highly-effective fluid chromatography - a tandem mass-spectrometry. The calculated percentage of distribution of the results of detection of content of testosterone by the ranges of expected values demonstrated an admissible comparativeness of obtained results from point of view of practical diagnostic. The choice of technique of detection of biochemical parameters in case of primary diagnostic is very important. However, even more important is the application of the very same technique in treatment and long-term observation of patient.

Postoperative hypocalcemia is a most frequent complication following thyroidectomy in the patients presenting with non-toxic multinodular goiter. It may require long-term hospitalization, additional treatment, a large number of analyses, and frequent visits to outpatient facilities. The objective of the present study was to identify the predictors of postoperative hypoparathyroidism for the prevention of the development of hypocalcemia and its medicamental correction. The clinical data were collected prospectively during the period from October 2011 till May 2013. A total of 140 patients were available for the observation after thyroidectomy performed for the management of non-toxic multinodular goiter. Indications for the surgical intervention included cervical compression syndrome and a cosmetic defect. The patients were divided into two groups depending on the serum calcium level in the postoperative period. Group 1 (n=45) was comprised of the patients having the serum calcium level 2.00 mmol/l or lower, group 2 (n=95) included the patients showing the serum calcium level above 2.00 mmol/l. In addition, serum 25(OH) vitamin D and parathyroid hormone (PTH) levels were measured in all the patients pre- and postoperatively. The preoperative 25(OH)D level and postoperative calcium and PTH levels in the patients of group 1 were significantly lower than in group 2 (p=0.001). It was shown that the main prognostic factors of postoperative hypocalcemia are the preoperative 25(OH)D level below 15 ng/ml (p<0.001), postoperative PTH level below 10 pg/ml (p=0.01), and the age above 50 years (p=0.01). It is concluded that in the majority of the patients the age, the low serum 25(OH)D level in the preoperative period, and the low postoperative PTH level are significantly related to the development of postoperative hypocalcemia.

Hyperprolactinemia associated with intake of neuroleptics (HAN) is a commonest endocrine disorder encountered in psychiatric practice. Approaches to the treatment of this condition remain to be developed. It is supposed that the use of dopamine receptor agonists may cause deterioration of the patients' psychic status. We have studied the influence of therapy with cabergolin on 44 patients presenting with HAN. It was shown that the long-term treatment using cabergolin is a safe and efficacious therapeutic modality for the patients suffering from psychic disorders. The frequency of exacerbation of psychic disorders in the group of patients treated with cabergolin was lower than in the control group. It is concluded that the correction of HAN by cabergolin in the patients presenting with psychic disorders leads to the significant improvement of reproductive and sexual functions.

This paper highlights the problem of neuroendocrine tumours (NETs) with clinical symptoms of hypercorticism caused by hypersecretion of adrenocorticotropic hormone (ACTH) by tumour cells. In most cases (85%), the tumours were localized in the pituitary gland (Cushing's disease); 15% of the patients had an extrapituitary tumour that manifest as an ectopic ACTH secretion (EAS). Comparative analysis of clinical, hormonal, histological, and immunohistochemical characteristics of pituitary and extrapituitary ACTH-secreting NET was performed. It included 46 patients with CD and 38 ones exhibiting ectopic ACTH secretion (EAS). Results of the study suggest differences between CD and EAS in terms of the severity of clinical manifestations and duration of the disease. Hormonal studies showed that EAS unlike CD was associated with high plasma ACTH and cortisol levels, late-evening salivary cortisol and daily urinary free cortisol, the absence of a 60% or greater reduction of cortisol in the HDDST test, and the presence of a low (less than 2) ACTH gradient in response to desmopressin administration with catheterization of cavernous sinuses. The study of morphofunctional characteristics of the removed NET demonstrated the ability of both pituitary and extrapituitary NETs to express ACTH as well as GH, PRL, LH, and FSH. The angiogenic markers (CD31 and VEGF) were detected with equal frequency regardless of the NET localization. The histological structure of all corticotropinomas suggested their benign origin, but extrapituitary NETs were represented by different morphological types with varying malignancy, invasiveness, and metastatic properties. A higher cell proliferation potential (Ki-67) was documented for NET in patients presenting with an ectopic ACTH secretion compared to those having corticotropinomas.

This study included the patients presenting with neuroendocrine tumours (NET) and the clinical picture of hypercoticism caused by excessive ACTH secretion from the tumour. The overwhelming majority of the patients (85%) suffered Cushing's disease (CD) associated with a pituitary tumour. The remaining 15% of the patients presented with ACTH-ectopic syndrome (ACTH-ES). The clinical picture of CD and ACTH-ES was very similar. The latter condition was associated with the higher plasma ACTH and cortisol levels as well as the free cortisol content in 24 hour urine and saliva samples collected in the evening compared with CD even though the differences were insignificant due to data scattering. Decompressin administration and catheterization of inferior petrosal sinuses caused a much greater enhancement of the ACTH level in the patients with CS in comparison with those suffering ASTH-ES.

Therapy with bisphosphonates (BP) is recognized to be "the golden standard" for the treatment of osteoporosis of different etiology. However, the data on the use of BP by the women during pregnancy and lactation are scarce. This paper reports a case of gestation, labour, and lactation in a patient treated with ibandronic acid (Bonviva) for severe steroid-induced osteoporosis attributable to Cushing's disease. To our knowledge, the application of ibandronic acid during pregnancy has never been described in the literature before. The present study has demonstrated that therapy with ibandronic acid does not necessarily require the interruption of pregnancy or cessation of birth feeding. Nevertheless, the treatment of the women of reproductive age with BP can be prescribed only upon strict indications.

The present study included patients with confirmed diagnosis of ACTH-dependent hypercorticism admitted to the Department of Neuroendocrinology and Osteopathies, Endocrinological Research Centre, between 2008 and 2012. Selective blood sampling from the inferior petrosal sinuses was performed with the stimulation by decompressin administered intravenously at a dose of 8 mcg. The normalized ACTH/prolactin ratio was calculated by dividing the maximum ACTH gradient following decompressin stimulation by the ipsilateral prolactin gradient. The cut off values were calculated from the operating characteristic curves as follows: 1.5 for the prolactin gradient (sensitivity 92.5%, specificity 100%) and 1.18 for the normalized ACTH/prolactin ratio (sensitivity 85.9%; 95% CI 76.8-93.4, specificity 100%; 95% CI 60.9-100). In the study cohort (n=70), the normalized ACTH/prolactin ratio proved to be a more specific but less sensitive parameter than the routine analysis of the ACTH gradient (sensitivity 98.4%, specificity 83.3%). Areas under the operating characteristic curves were on the whole identical. However, comparison of the diagnostic value of selective blood sampling from the inferior petrosal sinuses in combination of the determination of the prolactin gradient and normalized ACTH/prolactin ratio with the results obtained in the patients in whom the catheter position was not controlled (n=47) revealed the advantages of the former approach in terms of both the number of unverified causes of hypercorticism (1 versus 6) and the area under the operating characteristic curves 0.964 (95% CI 0.897-1.032) among 70 patients and 0.910 (95% CI 0.821-0.998) among the first 47 patients (included in the analysis confined to the confirmed cases). It is concluded that the determination of the prolactin gradient and calculation of the normalized ACTH/prolactin ratio allow to increase the diagnostic value of selective blood sampling from the inferior petrosal sinuses under decompressin stimulation. This inference is especially true of doubtful cases.